Third-Degree Injuries: Weeks 1 to 3

The treatment of third-degree medial ligament injuries involves short-term immobilization to allow the medial ligament structures time to heal with the least elongation or laxity by limiting medial joint opening and external tibial rotation. The lower limb is placed in a cylinder cast positioned in slight varus and internal rotation for 1 week to allow the disrupted medial soft tissues to “stick-down.” Plaster immobilization is required because a soft hinged or functional brace, even if locked at 0°, does not provide sufficient protection to maintain medial joint line closure to allow close approximation of the disrupted medial ligament and meniscus attachment soft tissues. The patient is instructed to maintain the leg in an elevated position with the limb supported in order to control lower extremity swelling. The patient is also instructed to stay off of the lower limb as much as possible. In addition, ankle-pumping exercises are performed to maintain lower extremity circulation, and quadriceps isometrics are done hourly. Electrical muscle stimulation (EMS) is used to augment the voluntary quadriceps contraction. Windows may be cut into the cast in order to observe the electrodes to ensure that they do not irritate the skin or to determine whether they need to be replaced. EMS is used approximately six times per day for 15-minute sessions. A co-contraction should occur between the stimulator and the patient’s voluntary contraction. Hamstring and gastrocnemius flexibility exercises are also encouraged to promote posterior muscle relaxation.

At 7 to 10 days, the cylinder cast is split into an anterior and a posterior shell (Fig. 25-2) to permit the patient to begin passive range of motion (ROM) exercises, which are initially assisted by the therapist. The cast is used for an additional 2 weeks to allow for early stick-down of the medial ligament structures. The patient is allowed to bear 25% of her or his body weight as long as the cast is in place. ROM exercises are initiated in a figure-four position from 0° to 90° in order to avoid valgus and external rotation loads on the healing ligaments (Fig. 25-3). A 4-inch tubular stocking is double-wrapped around the foot and ankle to allow the patient under her or his own power to flex the knee. This protected ROM program is performed three to four times a day for 10 to 15 minutes per session. Quadriceps strengthening exercises including isometrics and flexion straight leg raises are emphasized. TheraBand resistance for plantar flexion is used to maintain gastrocnemius tone. Ice, compression, and elevation are used for pain and swelling control.

Figure 25-2 Cylinder cast split into an anterior and a posterior shell.

Figure 25-3 Patient performs range of motion (ROM) exercises from 0° to 90° in a figure-four position with the hip joint externally rotated to protect the healing medial tissues.

Critical Points CONSERVATIVE TREATMENT OF MEDIAL LIGAMENT INJURIES

• First- and second-degree medial ligament injuries treated initially with a functional brace, weight-bearing as tolerated, and the rehabilitation program summarized in Tables 25-1 and 25-2.

• Third-degree medial ligament injuries require short-term immobilization to allow structures time to heal.

• Weeks 1–3

Cylinder cast 7–10 days.

Cast bivalved into anterior, posterior shell, worn 2 more wk. Knee motion done in figure-four position, 3–4 times/day.

Quadriceps isometrics, flexion straight leg raises.

• Weeks 4–6

Cast discontinued, functional brace worn.

Weight-bearing progressed 25%/wk, discontinue crutches by 6th wk.

Straight leg raises, closed-chain exercises.

Emphasis on ligament protection during gait and exercise.

• Weeks 7–9

Gait and range of motion normal or nearly normal.

Emphasis on returning lower extremity strength to normal.

Begin cross-training for cardiovascular endurance.

Balance, proprioception exercises.

• Weeks 10–12

Focus on return to activity.

Gait, knee motion, activities of daily living, symptoms should be within normal limits.

Isokinetic muscle strength parameters within 70% and 90% for straight-ahead running and more strenuous turning/cutting drills, respectively.

Full running program, sports-specific training.

• Concomitant anterior cruciate ligament (ACL) rupture and third-degree medial ligament rupture requires initial stick-down program and treatment described. 3–6 wk of conservative management before ACL reconstruction.

• Concomitant posterior cruciate ligament rupture and medial ligament rupture requires initial stick-down program with a posterior calf pad to prevent posterior tibial subluxation. Hamstrings contractions not allowed for 6 wk, then permitted in the active mode only for an additional 6 wk.

Third-Degree Injuries: Weeks 4 to 6

At the end of the first 3 to 4 weeks, the bivalved cast is discontinued and the patient is placed into either a functional knee brace (for medial ligament unloading) or a long-leg ROM brace depending on the extent of the knee effusion and residual tenderness to medial soft tissue pressure. A functional osteoarthritis brace is encouraged in order to avoid the expense of a transitional brace; however, this determination is based on each individual patient. Weight-bearing is progressed approximately 25% each week in order to discontinue crutches by the 6th week. Gait retraining is encouraged to allow for return of the normal reciprocal gait pattern (sufficient push-off during toe-off, midstance quadriceps contraction, hip and knee flexion during swing, and an upright posture).

Cryotherapy and EMS are continued in order to maintain control of pain and swelling as well as quadriceps reeducation. Exercises include quadriceps isometrics and straight leg raises in the flexion and prone positions through the 4th week. Abduction and adduction leg raises may then be initiated as long as there is sufficient quadriceps control to limit varus/valgus loading. Any resistance in a side-to-side fashion is kept above the knee through at least the 6th week. Closed-chain exercises such as standing calf raises and wall-sitting isometrics are encouraged. ROM is progressed with figure-four protection continued through the 4th to 6th week.

Emphasis during this time period focuses on ligament protection during gait and exercise. The progression of exercise allows knee motion to be restored within normal limits. Muscle strengthening includes both closed-chain and table exercises (straight leg raises). Emphasis is placed on hip and core control plus progression of quadriceps strengthening (Table 25-3).

Third-Degree Injuries: Weeks 7 to 9

If a long-leg brace was used in the previous phase, a functional brace is now initiated. Patients who already have a functional brace maintain its usage for ambulation. Gait and ROM should be normal or nearly normal, with restoration to normal as soon as possible. Pain and swelling should be within normal limits. Emphasis during this phase of treatment is on returning lower extremity strength to normal and to begin cross-training for cardiovascular endurance. Balance and proprioception exercises are also important components of this phase (see Chapter 13, Rehabilitation of Primary and Revision Anterior Cruciate Ligament Reconstructions).

Straight leg raises in multiple planes with ankle weights are used for hip control. Ten pounds of resistance represents the target goal for these exercises. Progression of the closed-chain program includes performing calf raises off of the edge of a step or with weight added for resistance. Isometric wall-sits are done with a gradual increase in hold time and then with handheld weights added. TheraBand resistance is used with mini-squats and terminal knee extension. Gait retraining is done with a heavy elastic band positioned about the thighs. In addition, the patient is progressed to a machine-oriented program for leg-press (80°–10°), knee extension (90°–30°), seated hamstring curls (0°–90°), hip abduction/adduction, and calf presses.

Endurance training includes a stationary bicycle, elliptical cross-trainer, and/or aquatics for 20 to 30 minutes at least three times per week. Activities such as cutting or twisting that place valgus and external rotation torques on the lower extremity are still limited. Proprioception and balance training includes unidirectional exercises balancing on a rocker board and multidirectional activities such as a wobble board or balance board. Balance activities at home progress from tandem balance positioning to single-leg stance. Isokinetic testing is performed to measure quadriceps and hamstrings muscle strength. The goals for initiating a running program are at least 70% bilateral comparison for quadriceps and hamstrings torque–to–body weight ratios (based on age and gender) and a hamstring-quadriceps ratio of 60%.

Third-Degree Injuries: Weeks 10 to 12

The focus of this final phase is on return to activity. By this time period, gait, ROM, activities of daily living, and symptoms should be within normal limits. The exercise progression advocates return of isokinetic muscle strength parameters within 70% and 90% for straight-ahead running and more strenuous turning/cutting drills, respectively. The cross-training program is advanced to a full running program that then allows for sports-specific training. Distance and direction-specific running and agility drills are incorporated. Heavy strength training occurs on opposite days of the running program. Injury prevention and neuromuscular retraining programs include jump-training activities with emphasis on technique, position, alignment, and repetition as discussed in detail in Chapter 19, Decreasing the Risk of Anterior Cruciate Ligament Injuries in Female Athletes. Isokinetic testing is performed, with the goal of achieving a 90% bilateral comparison for quadriceps and hamstrings torque–to–body weight ratios (corrected for age and gender), and a hamstring-to-quadriceps ratio of 60% at 120°/sec. Patients continue brace use for activity only. Follow-up treatment is based on the need for symptom control and/or functional progression for unrestricted return to activity.

Concomitant Cruciate Ligament Injuries

Patients who have a concomitant ACL rupture and third-degree medial ligament rupture undergo the initial stick-down program and treatment described. According to the severity of the medial collateral ligament (MCL) injury, sufficient time is required to stick down the medial structures, allow for figure-four ROM, protect with partial weight-bearing, and initiate early quadriceps exercises. Initial knee motion goals are 0° to 90°. Normally, 3 to 6 weeks of conservative management is required before the patient undergoes ACL reconstruction. The progression of exercises and weight-bearing is consistent with that described earlier.

Patients who have a concomitant PCL rupture and medial ligament rupture also undergo the initial stick-down program with a posterior calf pad to prevent posterior tibial subluxation. The cast is used for 4 weeks, followed with a long-leg brace with a posterior pad, which is used for 4 weeks. Then, weight-bearing, range of knee motion, and quadriceps exercises are progressed. Figure-four ROM exercises with an anterior drawer support allow for protection of both ligaments. The initial knee motion goal is 0° to 90°, which is then gradually progressed to full 6 weeks after cast wear. Full weight-bearing is permitted after 6 weeks, with emphasis on quadriceps control. Hamstrings contractions are not allowed for the initial 6 weeks and are then permitted in the active mode only for an additional 6 weeks. The patient’s gait, knee motion, quadriceps control, and symptoms should be back to normal limits in order to consider surgical intervention. Knee injuries with combined third-degree medial ligament ruptures and PCL ruptures often require operative repair; the postoperative course is described in Chapter 23, Rehabilitation of Posterior Cruciate Ligament and Posterolateral Reconstructive Procedures.

Modalities

In the immediate postoperative period, knee effusion must be controlled to avoid the quadriceps inhibition phenomenon. Electrogalvanic stimulation or high-voltage EMS may be used along with ice, compression, and elevation to control swelling. Treatment duration is approximately 30 minutes, the intensity is set to patient tolerance, and the treatment frequency is three to six times per day.

Once joint effusion is controlled, functional EMS is used for quadriceps muscle reeducation based on the evaluation of quadriceps muscle tone. One electrode is placed over the vastus medialis oblique (VMO) and a second electrode is placed on the central to lateral aspect of the upper third of the quadriceps muscle belly. The treatment duration is 20 minutes. The patient actively contracts the quadriceps muscle simultaneously with the machine’s stimulation.

Biofeedback therapy is important to facilitate an adequate quadriceps muscle contraction early postoperatively. The surface electrode is placed over the selected muscle component to provide feedback to the patient and clinician regarding the quality of active or voluntary quadriceps contraction. Biofeedback is also useful in enhancing hamstring relaxation if the patient has difficulty achieving full knee extension owing to knee pain or muscle spasm. The electrode is placed over the belly of the hamstring muscle while the patient performs ROM exercises.

Cryotherapy is begun in the recovery room after surgery. The standard method of cold therapy is an ice bag or commercial cold pack, which is kept in the freezer until required. Empirically, patients prefer motorized cooler units. These units maintain a constant temperature and circulation of ice water through a pad, which provides excellent pain control. Cryotherapy is used from three times a day to every waking hour for 20 minutes at a time depending upon the extent of pain and swelling. Cold therapy is typically done after exercise or when required for pain and swelling control and is maintained throughout the entire postoperative rehabilitation protocol.

Postoperative Bracing

Immediately after surgery, patients are placed into a long-leg postoperative brace that is locked at 0° extension for 2 weeks until the initial postoperative pain has receded and return of lower limb muscle control occurs. At this time, the brace is unlocked and the patient taught to resume a normal gait, with flexion during the stance phase, under 25% of body weight. After 6 weeks, the long-leg brace is stopped and a functional off-the-shelf brace is used. In select knees in which extensive surgery was performed and additional protection indicated, a custom medial unloading brace is prescribed for at least the 1st year postoperative.

Weight-Bearing

Patients are kept non–weight-bearing for the first 2 weeks. Then, toe-touch to 25% of the patient’s body weight is permitted from weeks 3 to 4. Partial weight-bearing is allowed as long as pain and swelling are controlled and a voluntary quadriceps contraction is demonstrated. The patient is taught to walk with a toe-in gait and avoid a toe-out valgus position. The therapist should observe the gait cycle for any tendency for a valgus thrust or external tibial rotation, which requires immediate correction to avoid placing excessive loads on the MCL repair or graft reconstruction. Weight-bearing is slowly progressed to full by the 7th to 8th week.

Range of Knee Motion

The goal in the 1st postoperative week is to obtain 0° to 90°. A continuous passive motion machine is not required. Patients perform passive and active ROM exercises in a seated position for 10 minutes a session, approximately four to six times per day. Initially, the therapist performs this exercise by applying a mild amount of varus and internal tibial rotation stress during flexion to unload the medial compartment (Fig. 25-4). Full passive knee extension must be obtained immediately to avoid excessive scarring in the intercondylar notch and posterior capsular tissues. It is important to note that patients undergoing SMCL repair or reconstruction are at an increased risk for developing a knee motion problem postoperatively.⁵ Supervision and close monitoring of the patient’s progress by the therapist is essential to avoid a potential arthrofibrotic response. If the patient has difficulty regaining at least 0° by the 7th postoperative day, an overpressure program is begun as described in detail in Chapter 13, Rehabilitation of Primary and Revision Anterior Cruciate Ligament Reconstruction, and 41, Prevention and Treatment of Knee Arthrosis. Overpressure exercises and modalities include hanging weight, extension board, and a drop-out cast (Fig. 25-5).

Figure 25-4 Early postoperatively, the therapist performs knee motion exercises by applying a mild amount of varus and internal tibial rotation stress during flexion to unload the medial compartment.

Figure 25-5 Extension overpressure exercises. A, Hanging weight. B, Extension board. C, Drop-out cast.

Knee flexion is gradually increased to 130° by the 7th to 8th postoperative week. Passive knee flexion exercises are performed initially in the figure-four position. Other methods to assist in achieving flexion include chair-rolling, wall-slides, commercial devices (Fig. 25-6), and passive quadriceps stretching exercises.

Figure 25-6 Flexion overpressure exercises. A, Rolling stool. B, Wall-slides. C, Commercial device.

Patellar Mobilization

Maintaining normal patellar mobility is critical to regain a normal range of knee motion. The loss of patellar mobility is often associated with arthrofibrosis and, in extreme cases, the development of patella infera.^6–8 Patellar glides are performed beginning the 1st postoperative day in all four planes (superior, inferior, medial, and lateral) with sustained pressure applied to the appropriate patellar border for at least 10 seconds (Fig. 25-7). This exercise is performed for 5 minutes before ROM exercises. Caution is warranted if an extensor lag is detected, because this may be associated with poor superior migration of the patella, indicating the need for additional emphasis on this exercise. Patellar mobilization is performed for approximately 12 weeks postoperatively.

Figure 25-7 Patellar mobilization.

Flexibility

Hamstring and gastrocnemius-soleus flexibility exercises are begun the 1st day postoperatively. A sustained static stretch is held for 30 seconds and repeated five times. These exercises help control pain due to the reflex response created in the hamstrings when the knee is kept in the flexed position. As well, the gastrocnemius-soleus towel-pulling exercise can help lessen discomfort in the calf, Achilles tendon, and ankle. Quadriceps and iliotibial band flexibility exercises are initiated at week 9. The flexibility program is maintained throughout the course of the rehabilitation program.

Strengthening

The strengthening program is begun on the 1st postoperative day. Early emphasis on the generation of a good voluntary quadriceps contraction is critical for a successful and safe return to functional activity. Isometric quadriceps contractions are completed hourly following the rules of 10-second holds, 10 repetitions, 10 times per day. Adequate evaluation of the quadriceps contraction by both the therapist and the patient is critical. If necessary, biofeedback can also be used to reinforce a good quadriceps contraction.

Straight leg raises are initiated the 1st postoperative day in the hip flexion plane. At weeks 7 to 8, the other three planes (adduction, abduction, and extension) are added to this exercise. As leg-raises become easy to perform, ankle weights are added to progress muscle strengthening. Initially, 1 to 2 pounds of weight are used and eventually; up to 10 pounds may be added as long as this is not more than 10% of the patient’s body weight.

Active-assisted ROM can also be used to facilitate the quadriceps muscle if poor tone is observed during isometric contractions. These exercises are primarily used during the first 8 postoperative weeks in which emphasis is placed on controlling pain and swelling, regaining full ROM, achieving early quadriceps control and proximal stabilization, and resuming a normal gait pattern.

Closed kinetic chain exercises are begun when partial weight-bearing of at least 50% is tolerated. Patients are instructed to avoid valgus loading during these exercises. These activities initially consist of mini-squats from 0° to 45°, toe-raises, and wall-sits. During the wall-sitting exercise, the patient may squeeze a ball between the distal thighs, inducing a hip adduction contraction and a stronger VMO contraction, or hold dumbbell weights in his or her hands to increase body weight (Fig. 25-8). The patient can also shift his or her body weight over the involved side to stimulate a single-leg contraction. The wall-sitting position should be held to a maximum burning of the quadriceps and repeated. This is an excellent exercise to mimic a stationary leg-press, achieve quadriceps muscle fiber recruitment, and induce muscle fatigue to build strength.

Figure 25-8 Strengthening exercises. A, Wall-sitting while squeezing a ball between the thighs. B, Wall-sitting while holding hand weights. C, Toe-raises. D, Lateral step-ups.

Lateral step-ups are begun when the patient has achieved full weight-bearing. The height of the step is gradually increased based on patient tolerance from 2 to 8 inches.

Hamstring curls are begun with Velcro ankle weights between weeks 9 and 12 and eventually advanced to weight machines. The patient exercises the involved limb alone, as well as both limbs together. Weight training is used throughout the program and continues in the return to activity and maintenance phases of rehabilitation.

Open kinetic chain extension exercises are incorporated within the first few weeks to further develop quadriceps muscle strength. Caution is warranted owing to the potential problems these exercises may create for the patellofemoral joint. Resisted knee extension is begun with Velcro ankle weights from 90° to 30° at postoperative weeks 3 to 4. The terminal phase of extension is avoided owing to the forces placed on the patellofemoral joint. The patellofemoral joint must be monitored for pain, swelling, and crepitus to avoid a conversion in which painful patellofemoral crepitus develops with articular cartilage damage. The surgeon should advise the therapist if patellofemoral joint damage was observed at surgery. The therapist should palpate the patellofemoral joint during active knee extension every therapy session to detect pain or an onset of joint crepitus. A patellofemoral conversion to a symptomatic state will occur in select knees, especially those with preexisting patellofemoral joint damage. In these knees, modification of the entire rehabilitation program is required.

A full lower extremity strengthening program is critical for early and long-term success of the rehabilitation program. Other muscle groups included in this routine are the hip abductors, hip adductors, hip flexors, and hip extensors. These muscle groups may be exercised on either a multi-hip or cable system machine or a hip abductor-adductor machine. Gastrocnemius-soleus strength is a key component for both early ambulation and the running program. In addition, upper extremity and core strengthening are important for a safe and effective return to work or sports.

Balance, Proprioceptive, and Perturbation Training

Balance and proprioceptive training are initiated when the patient achieves 50% weight-bearing. Initially, the patient stands and shifts weight from side-to-side and front-to-back. This activity promotes confidence in the leg’s ability to withstand the pressures of weight-bearing and initiates the stimulus to knee joint position sense. Cup walking is begun when the patient achieves full weight-bearing to promote symmetry between the surgical and the uninvolved limbs (Fig. 25-9).

Figure 25-9 Balance and proprioceptive training. A, Cup- (or cone-) walking. B, Single-leg balancing on an unstable platform. C, Walking on half foam rolls.

Double- and single-leg balance exercises in the stance position are beneficial and initiated during phases 5 to 6, depending on patient tolerance. During the single-leg exercise, the foot is pointed straight ahead, the knee flexed 20° to 30°, the arms extended outward to horizontal, and the torso positioned upright with the shoulders above the hips and the hips above the ankles. The patient remains in this position until balance is disturbed. A minitrampoline or unstable platform makes this exercise more challenging. The patient may assume the single-leg stance position and throw/catch a weighted ball against an inverted minitrampoline until fatigue occurs.

Perturbation training techniques are initiated during balance exercises. The therapist stands behind the patient and disrupts her or his body posture and position periodically to enhance dynamic knee stability. The techniques involve either direct contact with the patient or disruption of the platform the patient is standing on.

Walking on half foam rolls is also used in the gait retraining and balance program. This activity helps the patient develop balance and dynamic muscular control required to maintain an upright position and be able to walk from one end of the roll to the other. Developing a center of balance, limb symmetry, quadriceps control in midstance, and postural positioning are benefits obtained from this type of training.

Conditioning

Depending on accessibility, a cardiovascular program is begun as soon as the patient can sufficiently tolerate the upright position with an upper extremity ergometer. The surgical limb should be elevated to minimize lower extremity swelling. This exercise is performed as tolerated. Stationary bicycling is begun in the 5th to 6th postoperative week

Water-walking, swimming, and the use of an elliptical machine are allowed during the 9th to 12th postoperative weeks. Then, cross-country ski and stair-climbing machines are permitted. Protection against high stresses to the patellofemoral joint is strongly advocated. During bicycling, the seat height is adjusted to its highest level based on patient body size and a low-resistance level is used initially. Stair-climbing machines are adjusted to produce a short step and low resistance.

In order to improve cardiovascular endurance, the program should be performed at least three times per week for 20 to 30 minutes, and the exercise performed to at least 60% to 85% of maximal heart rate. It is generally regarded that performing in the higher levels of percentage of maximal heart rate achieves greater cardiovascular efficiency and endurance.

Running and Agility Program

In order to initiate the running program, the patient must demonstrate no more than a 30% deficit in average torque for the quadriceps and hamstrings on isokinetic testing and have no more than 3 mm of increase in medial joint opening (30° flexion). The majority of patients are at least 6 months postoperative.

The running program is based on the patient’s athletic goals, particularly the position or physical requirements of the activity, and is described in detail in Chapter 13, Rehabilitation of Primary and Revision Anterior Cruciate Ligament Reconstructions. The program is performed three times per week, on opposite days of the strength program. Because the running program may not reach aerobic levels initially, a cross-training program is used to facilitate cardiovascular fitness. The cross-training program is performed on the same day as the strength workout.

Plyometric Training

Plyometric training is begun upon successful completion of the running program in order to minimize alterations in neuromuscular function and proprioception. Important parameters to consider when performing plyometric exercises include surface, footwear, and warm-up. The jump training should be done on a firm, yet forgiving surface such as a wooden gym floor. Very hard surfaces like concrete should be avoided. A cross-training or running shoe should be worn to provide adequate shock absorption, as well as adequate stability to the foot. Checking wear patterns and outer sole wear will help avoid overuse injuries.

During the various jumps, the patient is instructed to keep his or her body weight on the balls of the feet. He or she should jump and land with the knees flexed and shoulder-width apart to avoid knee hyperextension and an overall valgus lower limb position. The patient should understand that the exercises are reaction and agility drills, and although speed is emphasized, correct body posture must be maintained throughout the drills. This program is described in detail in Chapter 13, Rehabilitation of Primary Revision Anterior Cruciate Ligament Reconstructions.

Once the patient has completed the running and plyometric programs and strength and function testing reach normal values, return to sports is allowed. A trial of function is encouraged in which the patient is monitored for knee swelling, pain, overuse symptoms, and giving-way episodes. Some athletes will experience transient knee swelling upon return to strenuous activities and should be educated on how to recognize this problem and the importance of reducing activities until the swelling subsides. If swelling persists, the athlete is advised to reduce athletics for 2 to 6 weeks, consider use of nonsteroidal anti-inflammatories, and use ice and elevation. Upon successful return to activity, the patient is encouraged to continue with a maintenance program. During the in-season, a conditioning program of two workouts a week is recommended. In the off-season or preseason, this program should be performed three times a week to maximize gains in flexibility, strength, and cardiovascular endurance.

During the entire functional progression, the therapist and surgeon should individualize the program based on the initial injury (particularly to the menisci and articular cartilage), magnitude of the operative procedure, and healing response of the patient. Athletes with loss of a meniscus or articular cartilage damage refrain from high-impact activities and are followed yearly to detect progression of the joint injury. These patients frequently have episodes of joint swelling and pain during the functional progression and are instructed to “play smart” and not be a knee abuser.